Multirotor Helicopters
A multirotor or multicopter is a rotorcraft with more than two lift-generating rotors. An advantage of multirotor aircraft is the simpler rotor mechanics required for flight control. Unlike single- and double-rotor helicopters which use complex variable pitch rotors whose pitch varies as the blade rotates for flight stability and control, multirotors often use fixed- pitch blades; control of vehicle motion is achieved by varying the relative speed of each rotor to change the thrust and torque produced by each. Due to their ease of both construction and control, multirotor aircraft are frequently used in radio control aircraft and unmanned aerial vehicle (UAV) (drone) projects in which the names tricopter, quadcopter, hexacopter and octocopter are frequently used to refer to 3-, 4-, 6- and 8-rotor rotorcraft, respectively. There is also the X8 (also called ''octo-quad'') configuration that is similar to the quadracopter design, except that it has eight rotors; the lower of whic ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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DJI Phantom 1 1530564a
SZ DJI Technology Co., Ltd. or Shenzhen DJI Sciences and Technologies Ltd. ( zh, c=深圳大疆创新科技有限公司, p=Shēnzhèn Dà Jiāng Chuàngxīn Kējì Yǒuxiàn Gōngsī) in full, more popularly known as its trade name DJI, which stands for Da-Jiang Innovations (), is a Chinese technology company headquartered in Shenzhen, Guangdong, backed by several state-owned entities. DJI manufactures commercial unmanned aerial vehicles (drones) for aerial photography and videography. It also designs and manufactures camera gimbals, action cameras, camera stabilizers, flight platforms, propulsion systems and flight control systems. DJI accounts for around 76% of the world's consumer drone market as of March 2021. Its camera drone technology is widely used in the music, television and film industries. The company's products have also been used by militaries and police forces, as well as terrorist groups, with the company taking steps to limit access to the latter. US govern ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Coaxial Rotors
Coaxial rotors or coax rotors are a pair of helicopter rotors mounted one above the other on concentric shafts, with the same axis of rotation, but turning in opposite directions (contra-rotating). This rotor configuration is a feature of helicopters produced by the Russian Kamov helicopter design bureau. History The idea of coaxial rotors originates with Mikhail Lomonosov. He had developed a small helicopter model with coaxial rotors in July 1754 and demonstrated it to the Russian Academy of Sciences. In 1859, the British Patent Office awarded the first helicopter patent to Henry Bright for his coaxial design. From this point, coaxial helicopters developed into fully operational machines as we know them today. Two pioneering helicopters, the Corradino D'Ascanio-built "D'AT3" of 1930, and the generally more successful French mid-1930s ''Gyroplane Laboratoire'', both used coaxial rotor systems for flight. Design considerations Having two coaxial sets of rotors provides sym ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Volocopter
Volocopter GmbH (formerly called E-Volo GmbH) is a German aircraft manufacturer based in Bruchsal (near Karlsruhe) and founded by Alexander Zosel and Stephan Wolf. The company specializes in the design of electric multirotor helicopters in the form of personal air vehicles, designed for air taxi use.Tacke, Willi; Marino Boric; et al: ''World Directory of Light Aviation 2015-16'', page 206. Flying Pages Europe SARL, 2015. The CEO is Florian Reuter and chairman Stefan Klocke. History 2011 The company flew the Volocopter VC1 and Volocopter VC2 technology demonstrators, followed by the two-seat Volocopter VC200 prototype. The VC1 was first flown on 21 October 2011. 2013 The two-seat project that became the Volocopter 2X started in 2013, evolved from early single-seat Volocopter VC2 prototype flown in 2011. The two seat prototype was designated as the VC-200 and the derived production model the 2X. An on-line fundraising effort in 2013 on the ''Seedmatch'' website raised €500 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Cierva Air Horse
The Cierva W.11 Air Horse was a helicopter developed by the Cierva Autogiro Company in the United Kingdom during the mid-1940s. The largest helicopter in the world at the time of its debut, the Air Horse was unusual for using three rotors mounted on outriggers, and driven by a single engine mounted inside the fuselage. Development The W.11 "Air Horse" heavy lift helicopter was developed by the G & J Weir, Ltd., Aircraft Department, reconstituted in 1943 as the Cierva Autogiro Company. The "W" in the designation is a continuation of the autogiro and helicopter series developed by G & J Weir, Ltd., during the period 1932–1940. The W.11 was a development of the Weir W.6 dual transverse rotor helicopter. It is the only helicopter of its type ever built and included three lifting rotors all turning in the same direction. The adoption of three rotors was due to concerns over the capability of a single large rotor to generate the required lift. Torque balance was provided by slightly ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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De Bothezat Helicopter
The de Bothezat helicopter, also known as the Jerome-de Bothezat Flying Octopus, was an experimental quadrotor helicopter built for the United States Army Air Service by George de Bothezat in the early 1920s, and was said at the time to be the first successful helicopter. Although its four massive six-bladed rotors allowed the craft to successfully fly, it suffered from complexity, control difficulties, and high pilot workload, and was reportedly only capable of forward flight in a favorable wind. The Army canceled the program in 1924, and the aircraft was scrapped. Development and testing Self-described as "the world's greatest scientist and outstanding mathematician",Young 1982, p. 36. and having written one of the first scientific papers on the aerodynamics of rotary-wing flight, George de Bothezat was a refugee from the Russian Empire who had fled to the United States in the wake of the Russian Revolution. Having written and lectured extensively on rotorcraft theory, de ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Transverse Rotors
Transverse rotor aircraft have two large horizontal rotor assemblies mounted side by side. Single-rotor helicopters (unicopters) need an additional tail rotor or tail exhaust to neutralize the reactional angular momentum produced by the main rotor. Transverse rotor helicopters, however, use counter-rotating rotors, with each cancelling out the other's torque. Counter-rotating rotor blades also won't collide with and destroy each other if they flex into the other rotor's pathway. In addition, transverse rotor configuration has the advantage of higher payload with shorter blades, since there are two sets working to provide lift. Also, all of the power from the engines can be used for lift, whereas a single-rotor helicopter must divert part of its engine power to generate tail thrust. Transverse rotor design with rotatable nacelles are known as tiltrotors while designs where the whole wing rotates are known as tiltwings. List of transverse rotor aircraft Transverse-mounted ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Tandem Rotors
Tandem, or in tandem, is an arrangement in which a team of machines, animals or people are lined up one behind another, all facing in the same direction. The original use of the term in English was in ''tandem harness'', which is used for two or more draft horses, or other draft animals, harnessed in a single line one behind another, as opposed to a pair, harnessed side by side, or a team of several pairs. The tandem harness allows additional animals to provide pulling power for a vehicle designed for a single animal. The English word ''tandem'' derives from the Latin adverb , meaning ''at length'' or ''finally''. It is a word play, using the Latin phrase (referring to time, not position) for English "at length, lengthwise". Tandem bicycles are named for their tandem seating, a more common arrangement than side-by-side "sociable" seating. ''Tandem'' can also be used more generally to refer to any group of persons or objects working together, not necessarily in line. Automob ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Tail Rotor
The tail rotor is a smaller rotor mounted vertically or near-vertically at the tail of a traditional single-rotor helicopter, where it rotates to generate a propeller-like horizontal thrust in the same direction as the main rotor's rotation. The tail rotor's position and distance from the helicopter's center of mass allow it to develop enough thrust leverage to counter the reactional torque exerted on the fuselage by the spinning of the main rotor. Without the tail rotor or other anti-torque mechanisms (e.g. NOTAR), the helicopter would be constantly spinning in the opposite direction of the main rotor when flying. Tail rotors are simpler than main rotors since they require only collective changes in pitch to vary thrust. The pitch of the tail rotor blades is adjustable by the pilot via the anti-torque pedals, which also provide directional control by allowing the pilot to rotate the helicopter around its vertical axis. Its drive system consists of a shaft powered from the mai ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Intermeshing Rotors
Intermeshing rotors on a helicopter are a set of two rotors turning in opposite directions, with each rotor mast mounted with a slight angle to the other, in a transversely symmetrical manner, so that the blades intermesh without colliding. The arrangement allows the helicopter to function without a tail rotor, which saves power. However, neither rotor lifts directly vertically, which reduces efficiency per each rotor. This configuration is sometimes referred to as a synchropter. Yaw is accomplished through varying torque, which is done by increasing collective pitch on one of the blade sets. Most intermeshing designs have two blades per mast, although exceptions such as the Kellett XR-10 with three blades per mast do exist. The arrangement was developed in Germany by Anton Flettner for a small anti-submarine warfare helicopter, the Flettner Fl 265 as the pioneering example, and later the Flettner Fl 282 Kolibri. During the Cold War the American Kaman Aircraft company pro ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Cyclorotor
A cyclorotor, cycloidal rotor, cycloidal propeller or cyclogiro, is a fluid propulsion device that converts shaft power into the acceleration of a fluid using a rotating axis perpendicular to the direction of fluid motion. It uses several blades with a spanwise axis parallel to the axis of rotation and perpendicular to the direction of fluid motion. These blades are cyclically pitched twice per revolution to produce force (thrust or lift) in any direction normal to the axis of rotation. Cyclorotors are used for propulsion, lift, and control on air and water vehicles. An aircraft using cyclorotors as the primary source of lift, propulsion, and control is known as a cyclogyro or cyclocopter. A unique aspect is that it can change the magnitude and direction of thrust without the need of tilting any aircraft structures. The patented application, used on ships with particular actuation mechanisms both mechanical or hydraulic, is named after German company Voith Turbo. Operating princip ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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The Hexacopter
''The'' () is a grammatical article in English, denoting persons or things already mentioned, under discussion, implied or otherwise presumed familiar to listeners, readers, or speakers. It is the definite article in English. ''The'' is the most frequently used word in the English language; studies and analyses of texts have found it to account for seven percent of all printed English-language words. It is derived from gendered articles in Old English which combined in Middle English and now has a single form used with pronouns of any gender. The word can be used with both singular and plural nouns, and with a noun that starts with any letter. This is different from many other languages, which have different forms of the definite article for different genders or numbers. Pronunciation In most dialects, "the" is pronounced as (with the voiced dental fricative followed by a schwa) when followed by a consonant sound, and as (homophone of pronoun ''thee'') when followed by a ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Rotorcraft
A rotorcraft or rotary-wing aircraft is a heavier-than-air aircraft with rotary wings or rotor blades, which generate lift by rotating around a vertical mast. Several rotor blades mounted on a single mast are referred to as a rotor. The International Civil Aviation Organization (ICAO) defines a rotorcraft as "supported in flight by the reactions of the air on one or more rotors". Rotorcraft generally include aircraft where one or more rotors provide lift throughout the entire flight, such as helicopters, autogyros, and gyrodynes. Compound rotorcraft augment the rotor with additional thrust engines, propellers, or static lifting surfaces. Some types, such as helicopters are capable of vertical takeoff and landing. An aircraft which uses rotor lift for vertical flight but changes to solely fixed-wing lift in horizontal flight is not a rotorcraft but a convertiplane. Classes of rotorcraft Helicopter A helicopter is a rotorcraft whose rotors are driven by the engine(s) throughout ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |